A conventional center stand, shown in FIGS. 1 and 2, comprises a main leg portion 10' having a trapezoidal shape when viewed from the rear of the motorcycle. The upper end of the leg portion is pivotably fixed to the lower frame 1 of the motorcycle in the approximate center of the motorcycle (not completely shown), so that the leg portion may pivot about 90 degrees between its perpendicular and horizontal positions. The main leg portion 10' is always urged or biased toward the horizontal position by a tension spring 14' connected between the leg portion and the frame 1. An operating lever 13' is fastened to one part 10a' of the leg portion in such a manner that it protrudes outwardly and rearwardly to facilitate erection of the stand by an operator.
In order to erect a center stand having the above construction, the main leg portion 10' must be rotated clockwise as seen in FIG. 1 from its horizontal position (not shown) against the force of the spring 14' until the lower end or foot of the main leg portion 10' reaches the ground. Then, the main leg portion 10' must be further rotated clockwise by engaging the operating lever 13' while lifting the motorcycle upwardly and rearwardly with the ground contact point as a fulcrum. In order to convert the stand from its erected position (FIG. 1) (for parking) to its horizontal position (for driving), the main leg portion 10' must be rotated counterclockwise (see dash-dot lines in FIG. 1) around the ground contact point at the lower end of the main leg portion 10' while pushing the motorcycle forwardly until the main leg portion 10' resumes its horizontal position with the aid of the spring 14'.
As will be obvious from the above discussion, it has been necessary to apply to the operating means 13' a force corresponding to the approximate total weight of the motorcycle when operating a conventional motorcycle stand. With a heavy motorcycle having a large displacement engine, therefore, such an operation has been an extreme burden to the rider.
To eliminate this inconvenience, it has been proposed, as described in Japanese Patent Provisional Pub. No. SHO 48-77548, to operate a stand by means of a hydraulic drive mechanism. Utilizing a hydraulic system provided on a motorcycle has, however, been found disadvantageous because it involves a complex construction, resulting in increased assembly processes and considerably higher cost.